To satisfy demands for wireless data traffic having increased since commercialization of 4th-generation (4G) communication systems, efforts have been made to develop improved 5th-generation (5G) communication systems or pre-5G communication systems. For this reason, the 5G communication system or the pre-5G communication system is also called a beyond-4G-network communication system or a post-long-term evolution (LTE) system.
To achieve a high data rate, implementation of the 5G communication system in an ultra-high frequency (mmWave) band (e.g., a 60 GHz band) is under consideration. In the 5G communication system, beamforming, massive multi-input multi-output (MIMO), full dimensional MIMO (FD-MIMO), an array antenna, analog beamforming, and large-scale antenna technologies have been discussed to alleviate a propagation path loss and to increase a propagation distance in the ultra-high frequency band.
For system network improvement, in the 5G communication system, techniques such as an evolved small cell, an advanced small cell, a cloud radio access network (RAN), an ultra-dense network, a device to device (D2D) communication, a wireless backhaul, a moving network, cooperative communication, coordinated multi-points (CoMPs), and interference cancellation have been developed.
In the 5G system, advanced coding modulation (ACM) schemes including hybrid frequency-shift keying (FSK) and quadrature amplitude modulation (QAM) modulation (FQAM) and sliding window superposition coding (SWSC), and advanced access schemes including filter bank multi carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) have been developed.
The SCMA is a codebook-based non-orthogonal multiple access technology and transmits a symbol corresponding to a multi-dimensional constellation. The SCMA has a lower error rate of a reception side, but a higher peak-to-average power ratio (PAPR) in a transmission side than OFDM.
Several methods have been proposed to reduce the PAPR, representative methods of which are clipping, companding, partial transmit sequence (PTS), selected mapping (SLM), etc. However, these methods have been studied based on orthogonal frequency division multiple access (OFDMA), and in spite of PAPR reduction, system complexity is increased or transmission of additional information is required, causing system load and signal distortion, thus resulting in system performance degradation. Therefore, a need exists for a scheme capable of reducing the PAPR caused due to the SCMA.